With the development of touch technology, capacitive touch devices have been widely used in mobile phones, tablet computers, computer displays, digital cameras and other electronic devices. In accordance with detection modes, the capacitive touch devices can be divided into self-capacitance touch devices and mutual-capacitance touch devices.
In a mutual-capacitance touch device, a touch function is mainly realized by two touch electrode layers (for example, a touch driving electrode layer and a touch sensing electrode layer), each touch electrode layer has a plurality of parallel touch electrodes, and the extension directions of two layers of touch electrodes intersect. A touch excitation signal is applied to the touch electrodes (touch driving electrodes) on one touch electrode layer, and when a finger contacts a screen of the touch device, the finger and certain touch electrodes on the screen form a coupling capacitor, and a leakage current flows out of the coupling capacitor. A touch sensing circuit determines two intersecting touch electrodes forming the coupling capacitor with the finger on the two touch electrode layers by detecting the leakage current so as to determine a touch position.
FIG. 1 shows a schematic diagram of a touch device in the prior art. As shown in FIG. 1, the touch device includes a plurality of touch sensing electrodes RE arranged in a first direction D1, a plurality of touch driving electrodes TE arranged in a second direction D2, a plurality of touch sensing electrode lines RL, a plurality of touch driving electrode lines TL and a driving circuit IC, the touch driving electrodes TE are connected to the driving circuit IC through the touch driving electrode lines TL, and the touch sensing electrodes RE are connected to the driving circuit IC through the touch sensing electrode lines RL. In one embodiment, the first direction D1 and the second direction D2 intersect.
Because the touch sensing electrodes RE extend in the second direction D2, the touch sensing electrode lines RL need wiring in a frame area on two sides of the touch device, in other words, the frame area with a certain width (e.g., hundreds of microns) needs to be reserved on the two sides of the touch device for wiring, resulting in that the frame on two sides of the touch device is widened, which is not favorable for the realization of a narrow frame.